The invention relates to an apparatus for the detection and processing of electric signals, consisting of a signal transmitter and a signal processing part, which are interconnectable in the signal path by means of a contact plug; and providing a galvanically separative coupling location in the signal path with primary and secondary coupling members.
Particularly in medical technology, it is common practice when tapping bio-signals to galvanically isolate the signal electrodes from the processing part by means of a coupling location. Thereby, an occurrence of possibly dangerously high leakage currents is to be prevented from the outset. An apparatus of this type with such a coupling location is known, for example, from the GB-LP No. 13 98 166. In this apparatus, the actual coupling location, which uses inductive (magnetic) transformers for the transmission of the actual use signal as well as for the energy transmission, is located outside of the actual processing apparatus in the line connection between the electrodes and the apparatus. In order to be put into operation, this coupling location as a complete component must first be plugged into the actual processing apparatus. This plug-type connection for the coupling location as a complete component also including the connection of the electrodes to the coupling location is, however, unsatisfactory, since, because of the very short air gap and leakage distances which are unavoidable in the desired compact design, the respective contact connection can hardly be insulated in terms of high voltage in the manner demanded by safety factors. The same also applies, however, to a heart-signal monitoring or processing apparatus as it is described in the periodical Electronics, Sept. 1, 1969, page 38. In this apparatus, the coupling location (again with inductive coupling for the transmission of use signal and energy) is, indeed, located in a common apparatus housing with the processing part. The actual EKG acceptance electrodes are then, however, connected directly through the apparatus housing to the coupling location, which then, therefore, gives rise to insulating problems at this passage through the housing.